Refrigerating apparatus



May 27, 1930. s. M. scHWELLER l,760,l75

REF-RIGERATING APPARATUS Filed Oct. 26, 1927 l L ff 16' f P# 2 Il 231 M W 17ML Patented May 27, 1930 UNITED STATES PATENT OFFICE SYLYESTER M. SCHWELLER, OF DAYTON, OHIO, ASSIGN OR, BY MESNE ASSIGNMENTS, TO FRIGIDAIRE CORPORATION, A CORPORATION OF DELAWARE REFRIGERATING .APPARATUS Application inea october 2e, 1927. serial No. '228,918.

, of being used in lieu of blocks of ice in refrigerators.

More specifically, it is among the objects of the invention to provide an improved rerigerating element of the type including finned refrigerant conveying ducts, in which the heat absorbing surfaces of the element are arranged to insure free circulation of air about the fins, and arranged so that the fins can be readily attached to the ducts, and so arranged that the entire surface of the iin is efliciently cooled.

Further objects vand advantages of the present invention will be apparent from the following description, reference being had to the accompanying drawing, wherein a pre'- ferred form of the present invention is clearly shown.v

' In the drawings:

Fig. 1 represents a side view in cross section of a display case refrigerator equipped with the refrigerating element of the inventon;

Fig. 2 is a top view of the refrigerating element, and

Fig. 3 isa side View of the same.

Referring in detail to the drawings the refrigerating element `rcooling unit comprises a header or tank 10 which4 in the type of refrigerating system selected for illustrating the preferred embodiment of the invention serves as a. means for receiving a refrigerating medium, preferably in liquid form, e. g., sulphur dioxide, and for distributing the same. to the other parts of the apparatus.

The refrigerating medium is led into the header 10 through duct 11. A suitable 'form l of float valve, not shown, may be used to maintain a constant level of refrigerant in the header. The vaporized refrigerant is led oft" from said tank through duct 12 which leads off from fthe spaceaho've the liquid level in the header.

The he'ader is provided with a plurality of cooling coils consisting essentially of a plurality of dependent ducts or'loops of pipe. These loops will be considered as constituting two series of loops, each including a plurality of sets of loops. One series of loops, referred to as series 13-14, comprises a plurality of sets of loops, each set including a loop 13 and a loop 14. Another series, referred to as series 15-16, comprises a plurality of sets of loops, each set including a loop 15 and a loop 16. The loops are connected in parallel to the header below the liquid level therein and depend below into the air cooled by said refrigerating element. The ducts are preferably flattened intheir dependent portion to facilitate attachment of ns and to increase their radiating surface while decreasing the refrigerant space.

Of the series 13-14, each loop 13 has a versubstantially .adjacent the vertical axis of.

header 10, and a second vertical leg 13" which is offset laterally a considerable distance from the same axis and which also depends downwardly from the header.

The other loops of the series 13-14 are indicated by the numeral 14; each loop has a vertical leg 14 depending downwardly but laterally offset from the header. The second vertical leg 14 of this loop depends downwardly substantially adjacent the vertical axis `of header 10. The loop series 15-16 has loops 15 of which a vertically depending leg 15 is` offset laterally from the header to a greater extent than leg 13 but not as much as leg 14 so that leg 15 in effect is really intermediate legs 14 and 13. The

-other leg 15 of loop 15 is disposed adjacent the header 10. Leg 15 is in the same plane as leg 14 and is therefore not visible in Fig. 3, although its top is shown in Fig. v2. Each loop 16' of series 15-16 likewise has a leg 16 disposed laterally Voffset to the header but not to the same degree as leg 13; leg 16 may therefore be said to be intermediate legs 14 and 13". The other leg 16" of loop 16 eX- tends vertically in the same manner on the opposite side of the header and is disposed the same distance from the vertical axis of the header as leg 15", It is not visible in Fig. 3

although its top is indicated by 16 in Fig. 2.

It will be observed that all of the loops marked 13 and 14 are bent up in the same shape but when they are attached to the header 10 alternate loops of a set are turned reversely so that the laterally offset legs 13 and 14 project alternately on opposite sides of the header.

Of the loop sets 13-14, each has a copper fin 17 attached thereto as by soldering or the like so as to insure good thermal connection between the loop and fin. Preferably the fins are soldered to the legs 13 and 14 at approximately the central portion of the iins The most laterally oiset loops 13 and 14 are preferably held in spaced relation by means of tie bars 18 which are soldered to the bottom of the loops. The lesslaterally disposed loops 14'. and 13 are held in a sufticiently rigid manner being substantially in the center of the tin Where they are subjected to less bending strain. Tie bars 19 may be used to keep the outer edges of the fins held in spaced relation.

It is thus apparent that the refrigerating element comprises a header, and a plurality of sets of dependent loops and tins, the fins being attached to the sets vhaving loops ex tendin' the greatest distance laterally either side oir the header. The space between the parallel dependent loop sets 13-14 is therefore occupied by a set of loops which bear no tins and the legs of Which are not extended laterally offset from the header to the same extent as the legs to which the lins are at,

tached.

It is also apparent that the loops of a given set are located in substantially the same plane, extending on either side of the header. A single lin made of a plane sheet of metal maytherefore be attached to both loops and preferably by soldering or otherwise uniting in good thermal contact the loop at one side of the header to one side of the fin and the loop at the other side of the header to the other side of the same iin. This construction facilitates assembly and imparts a symmetrical appearance and balance to the apparatus While obviating the use of a plurality of fins.

In the operation of the refrigerating elelnent the refrigerating medium in the vertically dependent legs absorbs heat from the circulating air and hence serves to cool the same. The ns aid in increasing the effective surface of the loops and direct the air currents. Due to lnoisture in the circulating air the loops and tins may become coated with frost which, if the fins are too closely spaced may bridge over between the fins. joining them with a network of ice which will hinder or prevent circulation of the air. By providing an intermediate set of loops e. g., the set 15h-16 without fins this disadvantage is obviated. The fins are thus maintained at a suitable distance from each other while the refrigerating eliiciency is not appreciably impaired. v

Fig. 1 shows the refrigerating element of the invention applied to a display case refrigerator Where its function is to serve 1n lieu of the ice blocks normally used for cooling food and particularly for causing an efiicient circulation of cold air within the 1nterior of the refrigerator.

The display case refrigerator shown in Fig. 1 comprises a base 2O provided with a suitable lining 21 and suitably insulated as With cork-board 22. Glass panels 23 are arranged at the sides and top of the case and preferably with air spaces 24 to serve as 1n sulation.

A top counter portion 25 similar in struc ing the header, loops and fins is mounted in the center of the interior of the display case as shown in Fig. 1.

Battles 26 of any suitable material are positioned at either side of the unit and the position of the batlles and distance of the unit from the bottom should be proportioned so as to permit of free circulation of air within the display case. It is apparent that the baiii'es 26, top section 25 and the central portion of the bottom 2l immediately below the refrigerating element as Well as the side walls (not shown) constitute a chilling chamber or cooling unit section and that the refrigerating element or unit when suitably mounted therein, as by brackets, not shown, serves the function normally played by a block of ice.

The arrows in ig. l illustrate the general circulation of the air in a display case equipped with the refrigerating element of the invention. The refrigerating element is placed in the position normally occupied by a block of ice. It is however, much more eicient than ice in that air may circulate unhindered between the parallel fins whereas in a block of ice the circulation is limited to the amount-of air which can lap the surfaces of the block.

As shown by the arrows in Fig. 1 the air cooled by the refrigerating element passes through the iues beneath the` battles and travels along the bottom of the food storage sections of the display case, cooling the article there displayed. Shelves or trays or the like may be disposed within the display case as shown diagrammaticallyI by the dotted lines, suitable provision being made for insuring circulation over and around the same such as by spacing the trays from the side Walls of the case or by using trays made of screening or the like. The air heated by its contact with the contents of the case passes upward and returns to the chilling chamber by means of the upper lues wherei't circulates between the channels formed by the fins.

While the form of' embodiment of the invention as herein disclosed, constitutes a preferred form, it is to be understood that other forms might be adopted, all coming within the-scope of the claims which follow.

What is claimed is as follows: 1. A refrigerating element for mechanical refrigerators comprising a header, a plurality of duct loops depending from said header and connected thereto in parallel, said loops being arranged in sets, certain of said sets each comprising loops of vertically depending legs substantially laterally offset from the vertical plane of the header, a fin for each of said sets, the fin of a set being thermally connected to each of the most laterally oii'set legs; and a set of loops intermediate said sets of finned loops, said latter set including loops having vertically depending legs offset laterally to a lesser degree than said legs of the first set.

2. A refrigerating element for mechanical-refrigerators comprising a header, a plurality of duct loops depending from said header and connected thereto in parallel, Said loops being arranged in sets, certain ofl said sets each comprising loops of vertically depending legs substantially laterally offset from the vertical plane of the header, the most laterally offset legs extending in close parallel planes, a fin for each of said sets, the fin of a set being in good contact with one side of one leg on, one side of the header 35 and with the other side of the corresponding leg on the opposite side of said header, and a set of loops intermediate'said sets of finned loops, said latter set including loops having vertically depending legs ofl'set laterally to 40 a lesser degree than said legs of the first set. 3. A refrigerating element for mechanical refrigerators comprising a header, a. plurality of duct loops depending from said header and connected thereto in parallel. said loops being arranged in sets, each set having two loops, each of the loops of one set having two substantially upright legs and a horizontal leg, lthe lhorizontal and upright legs of both loops lying in l`close par- E allel vertical planes'transverse to said header, each loop of said set having one leg offsetl laterally to a substantial degree from the vertical axis of said header, each loop of another set 'having a leg laterally offset to a lesser degree than the furthest laterally oi'set leg of the first set, and a fin attached to the first set in good Ythermal contact with each leg of said set.

v4., A refrigerating element for mechanical S0 refrigerators comprisin a header, .a plurality of duct loops depen ing from said header and connected thereto in parallel, said loops being arranged in sets, one set comprising a plurality of duct loops, each having vertical legs depending downwardly in the same lesser degree than the furthest offset legs ofsaid first set, a plurality of fins, each fin comprising a metal sheet lying in a parallel plane intermediate' the planes of all of the loops of one of the first sets and attached to 'said loops Ain good thermal contact.

5. A refrigerating element for mechanical refrigerators comprising a header, a plurality of parallel air circulating channels depending vertically from said header, and

extending substantially to equal distances tol both sides and underneath the header,`said channels being formed of duct loops depending from said header and arranged in sets and provided withl fins, one fin being attached to a set of dependent loops lying in parallel plane-i, said loops of a set each having a leg depending vertically substantially adjacent the header and another leg laterally offset to a substantial degree from said header, the space between said channels -be ing occupied by a similar set of duct loops of which the offset leg does not extend lat-- erally to the same extent as the finned sets of legs.

6. A refrigerating element for mechanical refrigerators comprising a header, a plurality of parallel air circulating channels depending vertically from said header, and

extending substantially to equal distances to both sides and underneath the header, said channels being formed of duct loops depending from said header and-provided with fins, one fin being attached to a plurality of depending loops lying in parallel planes, the space between said air c iannels being occupied bysimilar depending duct loops not provided with fins.

7. A cooling unit for mechanical refrigerators comprising a plurality of sets of duct loops, certain of said sets being each provided with a fin and certain other of said "sets heilig without fins, the loops of the finned set each in cludin a plurality of vertically extending legs, t 1e fin of the set being thermally connected with at least three of the vertical legs of the set, said certain other sets being interposed between and spaced from the finned sets.

8. A cooling unit for mechanical refrigerators comprising a plurality of sets of ducts, certain of said sets being each provided with a fin and certain other of said sets being without fins, the vducts of the finned sets being fashioned as loops, each having a plurality of vertically extending legs and each of said finned sets including a plurality of loops, the fin of the set being thermally connected with at least three ofthe vertical legs of the set, said certain other sets being interposed between and spaced from the finned sets.

9. A cooling unit for mechanical refrigerators comprising a plurality of setsvof ducts, each of said sets including at least three vertically extending legs, a in for each of Said sets thermally connected with at least three of said legs, and ducts Withoutiins interposed between and |spaced from the finned sets.

10. A cooling unit for mechanical refrigerators comprising a plurality of sets of ducts, each of said sets including at least three vertically extending legs, a fin for each of said sets thermally connected with at least three of said legs, said ducts being spaced along the iin, and ducts without fins interposed between and spaced from tliefinned sets.

11. A cooling unit for mechanical refrigerators comprising a plurality of sets of ducts, each of said sets including at least three vertically extending legs, iin means for-each set thermally connected with at least three legs of the set, and ducts without ns interposed between and spaced from the finned sets.

l2. A refrigerating element for mechanical refrigerators comprising an elongated header, a plurality of sets of duct loops connected with the header along the length thereofin parallel circuit relation, each provided with a iin, a plurality of ducts without fins con nected with the header along the length of the header and alternating with the first sets, the loops of the finned sets'each having a plurality of vertical extending legs, said fin being therinally connected to a plurality of legs of each loop in the set.

13. A refrigerating element for mechanical refrigerators comprising an elongated header, a plurality of sets of duct loops connected with the header along the length thereof in parallel circuit relation, each provided Y with a fin, a plurality of ducts without fins connected with the header along the length of the header and alternating with the first sets, the loops of the nned sets each having a plu-` rality of vertical extendin legs, one leg ot each set being more latera ly oiset from a vertical plane of the header than its other leg, said fin being thermally connected to both legs of each loop of a set. 14. A refrigerating element for mechanical refrigerators comprising an elongated header, a plurality of sets of duct loops connected with the header along the length thereof in parallel circuit relation, leach pro- 'vided with fin means, a'plurality of* ducts without fins connected with the header along the length of the header and alternating with the first sets, the loops of the finned sets each having a plurality of vertical extending legs,

said fin means bein thermally connected to nature.

SYLVESTER M. SCHWELLER. 

